4.13-stable review patch. If anyone has any objections, please let me know.
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From: Guillaume Nault g.nault@alphalink.fr
[ Upstream commit 5903f594935a3841137c86b9d5b75143a5b7121c ]
When pppol2tp_session_ioctl() is called by pppol2tp_tunnel_ioctl(), the session may be unconnected. That is, it was created by pppol2tp_session_create() and hasn't been connected with pppol2tp_connect(). In this case, ps->sock is NULL, so we need to check for this case in order to avoid dereferencing a NULL pointer.
Fixes: 309795f4bec2 ("l2tp: Add netlink control API for L2TP") Signed-off-by: Guillaume Nault g.nault@alphalink.fr Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/l2tp/l2tp_ppp.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/net/l2tp/l2tp_ppp.c +++ b/net/l2tp/l2tp_ppp.c @@ -993,6 +993,9 @@ static int pppol2tp_session_ioctl(struct session->name, cmd, arg);
sk = ps->sock; + if (!sk) + return -EBADR; + sock_hold(sk);
switch (cmd) {